Hyperion Focal Reducer

The optical design of the Hyperion focal reducer has been revised to take advantage of the longer mechanical backfocus available on the truss-tube versions of the Hyperion telescopes. The backfocus of the reducer now allows use of Apogee high-cooling camera bodies with filter wheel and MonsterMOAG guider. Also, the focal reduction factor has been improved, allowing a wider field of view and faster imaging.

This focal reducer has been custom-designed to match the excellent optical performance of the Hyperion astrograph. It retains a large, flat field, free from aberrations. In fact, performance is diffraction-limited over a full 52mm field of view.

With 4 inches of backfocus, the Hyperion focal reducer works with a variety of camera setups, including:

Apogee Alta Series*

Apogee Alta Series* with FW50 filter wheel

Apogee Alta Series* with FW50 and MonsterMOAG guider

Apogee Aspen Series

FLI Proline

FLI Proline with FLI CFW

QSI 500 Series

SBIG ST Series

SBIG STL Series

SBIG STL Series with FW8 filter wheel

SBIG STL Series with FW8 and MonsterMOAG guider

SBIG STX Series

Starlight Xpress SXVR

And many more...

* Including deep-cooling models

The focal reducer converts the 12.5" f/8 Hyperion to an f/5.7 focal ratio, and the 16" f/7.3 Hyperion to an f/5.2 focal ratio, making each nearly 2 times faster. The reducer is designed to cover a 52mm image circle, corresponding to the diagonal size of the popular KAF-16803 large-format CCD sensor. Large (76mm) lens elements keep the vignetting to less than 15% over the 52mm field.

The Hyperion focal reducer threads onto the end of the telescope's standard Feathertouch 3.5" focuser, in place of the normal end cap. A 3" flange forms the standard camera attachment. The Apogee Alta series with Apogee FW50 and Astrodon MonsterMOAG bolts directly to the flange. Other cameras require alternate adapters or spacers to keep the backfocus correct and keep the performance nominal. Adapters are available for a variety of cameras.